# NCBI BioProject E-Search

> NCBI BioProject E-Search is a paid API for AI agents from clonecho.builda.company, paid per call via x402, $0.02/call, status unknown (last checked 2026-09-14).

Search NCBI BioProject database and return matching project UIDs for a given query using E-utilities

## Facts

- Endpoint: POST https://clonecho.builda.company/x402/s/ncbi-esearch-bioproject
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/ncbi-bioproject-e-search-1f083fb2
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_qw3KTSA6EBMmFJoUOBkV-

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability ncbi-bioproject-e-search-1f083fb2 -d '<json body>'
```

Example prompt: Search NCBI BioProject for projects related to 'human gut microbiome metagenomics' and give me the matching project UIDs.

## When to prefer this

Use this endpoint when you need to programmatically search NCBI's BioProject database to find project UIDs for downstream retrieval of genomics or biological study metadata. Prefer this over direct NCBI API access when you need a simple paid-per-call interface without managing NCBI API keys or rate limits yourself.

## Known failure modes

- Empty result set if query matches no BioProject entries
- Malformed or ambiguous query may return irrelevant UIDs
- NCBI E-utilities rate limiting or downtime causing request failure
- Very broad queries may return truncated result sets
- Special characters in query string not properly URL-encoded causing 400 error

## How this service works

Search NCBI BioProject and return matching project UIDs for query {q} via E-utilities. Query: ?q= Returns JSON.

## Output

Returns a JSON object containing BioProject UIDs matching the search query, including result count and identifiers that can be used to fetch detailed project records from NCBI.

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/ncbi-bioproject-e-search-1f083fb2/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from clonecho.builda.company](https://www.zero.xyz/host/clonecho.builda.company/llms.txt)